How is the Third Law of Geography different?

Three overarching principles governing patterns of geographic phenomena have been proposed that have been referred to by some as ‘laws of geography’. The first and the second principles address the spatial proximity and spatial heterogeneity of geographic phenomena. These principles, while powerful, fail to resonate with much geographical inquiry. The more recently proposed third principle concerns geographic similarity. The differences of it from the first two can be perceived in three basic aspects: principle expressed, form of expression and role of geographic examples (samples). The third principle emphasizes the geographic context of geographic variables in the form of geographic configuration, compared to a single spatial dimension that are emphasized in the first two principles. The third principle focuses on the comparative nature in the geographic configuration in terms of similarity, that is, in the form of ‘similar to’, as opposed to the relationships ‘between’ that are key to the first and second principles. The third principle emphasizes the individual representation of geographic examples, as opposed to the global representation of geographic examples. These differences not only distinguish the third principle as an important addition to the other two, but also provide a potentially transformative way to address the rigid requirements on samples in geographic analysis, particularly during this age when the collection and provision of geographic data are crowd-sourced and VGI-based. These differences also point to the potential of the third principle opening up a space of inquiry that would resonate more successfully with place-based approaches in human geography.